Drying of Probiotics: Optimization of Formulation and Process to Enhance Storage Survival

Abstract

This work describes how probiotic bacteria can be dried at low temperature in two steps, combining spray drying and vacuum drying, in order to enhance their survival during storage. A sufficient number of dried probiotics survived storage for more than 3 months at 30°C, if an appropriate combination of protein and carbohydrate was selected as carrier and storage conditions were maintained optimal. The use of soy protein and maltodextrin or skim milk and arabic gum resulted in the best survival rates of probiotics during storage. No evident difference was found between different spray dryer configurations, although a cocurrent flow was preferred.

Keywords:

• Food powders
• Lactic acid bacteria
• Soy protein
• Spray drying
• Vacuum drying

Notes

SD = after spray drying, VD = after vacuum drying.